Clinical differences between alcoholic liver disease and nonalcoholic fatty liver disease

Table 1 Epidemiology of alcoholic liver disease and nonalcoholic fatty liver disease

	ALD	NAFLD	Ref.
Prevalence rate (overall)	Unclear	12.9%-46.0%	[8-12]
	(rates may reflect geographical differences in the amount of alcohol intake)
Prevalence rate (China)	4.50%	15.0%	[14]
Trend (Japan)		Increasing (12.6% in 1989; 28.4% in 2000)	[8]
Peak age	45-69 yr (United States)	40-49 yr in males; 60-69 yr in females (Japan)	[12,15]
		60-69 yr (China)	[16]
Gender	Male dominant	Male dominant	[11,12,18-20]
Ethnicity	South American males > Afro-Caribbean males	Hispanics > Whites > Blacks	[21,22]

ALD: Alcoholic liver disease; NAFLD: Nonalcoholic fatty liver disease.

Table 2 Rates of alcoholic liver disease and nonalcoholic fatty liver disease progression and the factors associated with susceptibility and progression

	ALD	NAFLD	Ref.
Rate of progression from simple hepatic steatosis to liver cirrhosis	1.0%-3.1% per year	0%-2.5% per year	[51-55]
Rate of progression from steatohepatitis to liver cirrhosis	3.2%-12.2% per year	1.3%-3.5% per year	[51-54]
Environmental factors associated with disease susceptibility	Increased alcohol intake	Increased calorie intake	[18,50,57]
	Daily heavy drinking, not episodic or binge drinking		[18,60]
		Fructose	[62]
Environmental factors associated with disease progression	Increased amount of alcohol intake	Higher intake of soft drinks and meats	[58,61]
	Spirits rather than beer or wine	Fructose	[59,62]
Host factors associated with disease susceptibility
Age	Older age		[65,66]
Gender	Female		[57]
Body mass index	Obesity	Obesity	[22,58,67]
Metabolic syndrome	Presence	Presence	[22,71,72]
Type 2 diabetes	Presence	Presence	[71,72]
Ethnicity	Hispanic, Black	Hispanic	[11,73,74]
Genetic variant	PNPLA3 rs738409 G	PNPLA3 rs738409 G	[80-84]
Host factors associated with disease progression
Age	Older age	Older age	[58,67,68]
Gender	Female	No difference	[52,55,58,67]
Body mass index	Obesity		[58,67]
Metabolic syndrome
Type 2 diabetes
Ethnicity
Genetic variant	PNPLA3 rs738409 G	PNPLA3 rs738409 G	[80-84]

ALD: Alcoholic liver disease; NAFLD: Nonalcoholic fatty liver disease.

Table 3 Outcome predictors in patients with alcoholic liver disease and nonalcoholic fatty liver disease

Outcomes	ALD	NAFLD	Ref.
Hepatocarcinogenesis
Underlying liver disease
Compensated cirrhosis	Not identified		[90]
Decompensated cirrhosis	Older age		[91]
Compensated/decompensated cirrhosis	PNPLA3 rs738409 G	Older age, any alcohol intake	[92-94]
	Not identified	Older age, elevated GGT, high CP score	[96]
Unknown stage		Older age, type 2 diabetes, elevated AST, low PLT	[95]
Hepatic decompensation
	Persistent alcohol intake		[90]
Mortality (overall)
Underlying liver disease
Simple hepatic steatosis	Low ALB, severe steatosis	Low ALB	[55]
Simple hepatic steatosis/steatohepatitis		Older age, type 2 diabetes	[101]
Advanced fibrosis/cirrhosis	Persistent alcohol intake, older age, smoking, low ALB	AST/ALT > 1, older age	[99,100]
Compensated cirrhosis	Persistent alcohol intake		[90]
Decompensated cirrhosis	Older age, alcohol abuse, elevated ALP		[97]
	Older age, persistent alcohol intake, low ALB, high MELD score		[98]
	Older age, poor liver function		[91]
Unknown stage		Metabolic syndrome, older age, smoking, Black	[102]
	Type 2 diabetes, insulin resistance	Type 2 diabetes, insulin resistance	[103]

ALD: Alcoholic liver disease; NAFLD: Nonalcoholic fatty liver disease; ALB: Albumin; ALP: Alkaline phosphatase; MELD: Model for end-stage liver disease; GGT: γ-glutamyl transpeptidase; CP: Child-Pugh; AST: Aspartate aminotransferase; PLT: Platelet; ALT: Alanine aminotransferase.

Table 4 Outcome characteristics of patients with alcoholic liver disease and nonalcoholic fatty liver disease

Outcomes	ALD	NAFLD	Ref.
Hepatocarcinogenesis
Incidence rate
Simple hepatic steatosis/steatohepatitis		0%-0.2% per year	[115]
Steatohepatitis/cirrhosis		0.3%-4.3% per year	[115]
Compensated cirrhosis	0.7% per year		[90]
Decompensated cirrhosis	1.4% per year		[91]
Compensated/decompensated cirrhosis	2.5% per year	2.1% per year	[96]
Unknown stage		0.043% per year	[95]
Prevalence rate of non-cirrhotic liver as underlying liver disease	5.3%-12.0%	25.0%-58.3%	[116-118]
Comparison of survival	Similar to non-ALD, NBNC HCC	Better than ALD- or HCV-related HCC	[119,120]
Hepatic decompensation
Incidence rate
Compensated cirrhosis	4.4% per year	4.5% per year	[90,121]
Mortality (overall)
Incidence rate
Simple hepatic steatosis	3.3% per year		[52]
Steatohepatitis	5.0% per year		[52]
Steatohepatitis/cirrhosis		1.8% per year	[100]
Compensated cirrhosis	3.2% per year		[90]
Decompensated cirrhosis	5.7%-6.0% per year		[91,97]
Compensated/decompensated cirrhosis		5.0% per year	[124]
Compared with liver diseases due to other causes		Similar to HCV-related compensated liver disease	[100]
	Similar to HCV-related compensated cirrhosis	Better than HCV-related compensated cirrhosis	[90,122]
	Similar to HCV-related decompensated cirrhosis	Similar to HCV-related decompensated cirrhosis	[91,122]
		Similar to HCV-related cirrhosis	[124]
Improved survival	Abstinence		[123]
Causes of death
Simple hepatic steatosis			[55]
Liver-related causes	17%	2%
Arteriosclerosis	20%	38%
Extrahepatic malignancy	14%	17%
Infection	3%	8%
Cirrhosis			[90,97,98,122,124]
HCC	10%-13%	6.9%-47.4%
Liver failure	25%-60%	17.2%-31.6%
Cardiovascular disease	1%	27.6%
Cerebrovascular disease	1%-4%
Infection	8.9%-25%	41.4%
Extrahepatic malignancy	8%-25%

ALD: Alcoholic liver disease; NAFLD: Nonalcoholic fatty liver disease; HCC: Hepatocellular carcinoma; NBNC: Non-B, non-C; HCV: Hepatitis C virus.